Hydraulic generator drive



Oct. 27, 1959 E. E. MURPHY HYDRAULIC GENERATOR DRIVE 6 Sheets-Sheet 1 Filed Jan. 9, 1957 J a 3 a a a TI lr w m m ww n m w H A FIG. I

VOLTAGE REGULATOR INVENTOR. EUGENE E MURPHY ATTERY ATTORNEYS Oct. 27, 1959 E. E. MURPHY HYDRAULIC GENERATOR DRIVE Filed Jan.

6 Sheets-Sheet 2 FIG.3

INVENTOR.

EUGENE E. MURPHY BY i ATTORNEYS Oct. 27, 1959 E. E. MURPHY HYDRAULIC GENERATOR DRIVE 6 Sheets-Sheet 3 Filed Jan. 9, 1957 INVENTOR. EUGENE E. MURPHY ATTORNEYS Oct. 27, 1959 E. E. MURPHY HYDRAULIC GENERATOR DRIVE 6 Sheets-Sheet 4 Filed Jan. 9, 1957 MN NR 0; O ooo OOOOOOOOwWWWN w INVENTOR. EUGENE E. MURPHY ATTORNEYS Oct. 27, 1959 E. E. MURPHY mmuuc GENERATOR DRIVE 6 Sheets-Sheet 5 Filed Jan. 9, 1957 TO PUMP IO FIG. 7

TO PUMP IO FIG.8

FROM FILTER 25 INVENTOR. EUGENE E. MURPHY ATTORNEYS Oct. 27, 1959 MURPHY 2,910,013

HYDRAULIC GENERATOR DRIVE Filed Jan. 8, 1957 6 Sheets-Sheet 6 FIG. 9

I /64 1! M3 M J J fl i 1 I M653 1 /66/] l H l w v. i I

M05 M55 //2 /62 /6/ M934 M04 FIG. I0 /57 I003 M73 674 MM INVENTOR. EUGENE E. MURPHY ATTORNEYS HYDRAULIC GENERATOR DRIVE Eugene E. Murphy, Omaha, Nebr., assignor to American Brake Shoe Company, New York, N.Y., a corporation of Delaware Application January 9, 1951, Serial No, 633,351 1 Claims. c1. 105-.-.-96.1)

There are a number of applications in which it is de- Sirable to afford electrical power for lighting and other similar purposes on railway or other rolling stock. The requirements of such applications may of course be fulfilled by engine-powered generators with suitable control equipment; on the other hand, and particularly in railway applications, space limitations and other factors frequently make the use of an engine-generator set undesirable. A typical example of this sort of application is the caboose employed to carry the personnel on a railway freight train; in this instance, space is at a premium. Moreover, in this instance the fire hazards such as are often presented by the fueling arrangements on engine-generator sets [are highly undesirable, since a fire in the caboose can be extremely dangerous both to the personnel involved and to the train.

Numerous systems have been proposed in the past for providing electrical power from a generator driven directly or indirectly from the wheels of a railway car. There are several difliculties inherent in a system of this type, the principal problem presented being that caused by reversal of the direction of motion of the car which effectively reverses the direction of rotation or movement of the prime power source. Although numerous schemes have been presented for avoiding this difficulty, none of the known systems has achieved general commercial acceptance. Previously proposed driving systerns of this type have been generally undesirable because of excessive mechanical complication, at least in many instances. Moreover, they have frequently required the coupling of relatively bulky drive-conversion units to the car axle, thereby minimizing any advantages the systems might otherwise possess with respect to an engine-generator set.

It is an object of the invention, therefore, to provide a new and improved driving or actuating system for an electrical generator in a railway car.

Another object of the invention is to provide a means for driving an electrical generator from the wheel or axle of a railway car and for maintaining rotation of the electrical generator constant in direction irrespective of the direction of movement of the car. i

It is a more specific object of the invention to providea new and improved hydraulic actuating system for an electrical generator in a railway car which effectively rotates the generator in a given direction despite the fact that the actuating pump of the system may be reversed in its direction of operation.

An additional object of the invention is the provision of a new and improved mounting arrangement for a hydraulic pump which permits the pump to be supported directly on the journal of a railway car. without interfering in any way with operation of the car.

United States PatentQ on the car, and requires a minimum of maintenance.

Accordingly, the invention is directed to an electrical generating system for use in conjunction with an electrical distribution system in a railway car or like vehicle and comprises a generator electrically coupled to the diS- tribution system and a fluid motor coupled in mechanical driving relationship to the generator.. A drive shaft is mechanically coupled to a journal or axle of the vehicle for rotation therewith, a drive gear being mounted on the drive shaft. The generating system further includes a fluid pump which is operable by rotation of a pump shaft and a pinion gear mounted on the pump shaft in ieshing engagement with the drive gear for rotation therewith. Fluid coupling means are provided for interconnecting the pump and the motor to deliver fluid under pressure from the pump to the motor to actuate .the motor for rotation in a given direction independent of the direction of rotation of the drive and pump shafts.

Other and further objects of the present invention will be apparent from the following description'and claims and are illustrated in the accompanying drawings which, by way of illustratiomshow a preferred embodiment of the present invention and the principles thereof and what I now consider tobe the best mode in which I have contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without .departing from the present'invention and the purview of the appended claims.

In the drawings:

Fig. 1 is a schematic diagram of the driving apparatus for an electrical generating system constructed in accordance with one embodiment of the invention;

Fig. 2 is a schematic wiring diagram of a typical electrical distribution system which may be used in conjunctiOIl With the invention;

Fig. 3 is a cross-sectional elevation view of a pumpmounting arrangement embodying a principal feature of the invention; t

Fig. 4 is a plan view, partly cut away to show certain of the operating parts, of the. apparatus of Fig. 3;

Fig. 5 is an elevation view of a hydraulic system which constitutes one specific example of the motor and motor control apparatus of Fig. 1;

Fig. 6 is a plan view of the apparatus of Fig. 5;

Fig. 7 is an end view of the apparatus of Fig. 5

taken along line 7 7 therein;

control of an electrical generator to be mounted'on av railway car. The driving system includes a reversible hydraulic pump 10 which is mechanically coupled to the 'journal of a railway car wheel 11 through a gear box 1'2, the journal not appearing in this particular view. The hydraulicsystem includes fluid coupling means comprising a manifold 13 which links pump ltl'to a fluid motor 14 and to a fluid reservoir 15. Thus, one of the inlet-outlet ports 16 of pump 10 is connected to motor 14 through a check valve 17 and to reservoir 15 through a second check valve 18. Similarly the second inlet-outlet port 19 of the pump is hydraulically coupled to motor 14 which is returned to reservoir 15. a drain port 23 which is also returned to the reservoir.

An outlet port 24 on the motor is connected through a filter 25 to the inlet port 26 on a booster pump 27 which and to the reservoir through is mounted within reservoir 15. A vent or drain line 128 also connects the filter back to reservoir 15. The

outlet port 29 of booster pump 27 is connected to valves 18 and 21 to provide oil for the system. The booster pump also includes a second inlet port 30 within the reservoir; the construction and operation of the booster "pump are described in greater detail hereinafter in connection with Fig. 8.

An understanding of the operation of the hydraulic systern illustrated in Fig. 1, to be complete, preferably entails consideration of cerain of the operating characteristics of individual units in the system. In particular, pump comprises a reversible pump capable of operation over a Iwide range of speeds. A preferred type of pump which has been found to afford superior service in this system comprises a single-stage vane-type dual-purpose unit,v 'manufactured by the Denison Engineering Company of Columbus, Ohio.

This particular pump is sold under the designation Hydroilic Pump/Motor; the particular model which has been found most suitable carries the model designation TMC-3FX208, although a number ofother pumps of this general type are also suitable for service in the system. Motor 14, on the other hand, is

' an essentially similar unit and may be. selected from the same line of pump/motor devices by the same manufacturer, in which instance the model TMB-12F pump motor is preferred. Check valves 17, 18, 20, and 21 may be of j conventional construction, as may relief valve 22. In this connection, it should be noted that the individual valves, particularly the check valves, may be replaced by a unitary four-way valve structure for controlling the direction of flow of the oil; a preferred valve apparatus of this type is described and claimed in the co-pending application of Joseph H. Caslow, Serial No. 448,700, filedAugust 9,

' 1954, now Patent No. 2,809,652, issued October 15, 1957, and assigned to the Denison Engineering Company.

Booster pump 27 is provided in the system to maintain the oil supply lines to the pump completely filled with the hydraulic fluid and comprises a simple jet-type pump as will be described more completely hereinafter. Filter 25 may be of completely conventional construction, as may be electrical generator 32 of the system, which is mechanically connected to the fluid motor 14.

'of the coupling gears in gear box 12 and construction I of the pump. Under these circumstances, oil is pulled from reservoir through booster pump 29 and check valve 18 into pump 10. The oil is forced under pressure out of port 19 and through valve into the inlet port 33 of motor 14, driving the fluid motor in a predetermined direction and thus driving generator-32 in a preselected direction. The oil under pressure from the pump cannot return to the reservoir, since check valve 21 does not permit oil flow in that direction. The oil exhausted from pump 14, which is still under pressure although .the pressure has been reduced, is returned to booster pump 27 through inlet port 26 to operate the booster .pump and assure complete filling of the inlet line to port 16 of main pump 10. This is highly desirable in order to avoid cavitation within pump 10. If the main pump 10 is driven at an extremely high speed, due to high speed operation of the railway car on which wheel 11 construction and needs no further description. .over, as best shown in Fig. 3, journal 50 is provided with is mounted, the resultant excess volume of the oil from outlet port 19 is by-passed by relief valve 22 before the oil is supplied to the fluid motor 14, should the load on the fluid motor become excessive. In this connection, it should be noted that the oil under pressure cannot flow back to inlet port 16 through check valve 17, since the check valve does not permit oil flow in this direction.

Assuming that the direction of motion of the car to which wheel 11 is attached is reversed, the Wheel is then rotated in the direction indicated by arrow B. Under these circumstances, the system remaining otherwise unchanged, port 19 of pump 10 becomes the suction port of the pump and port 16 functions as the outlet or pressure'port. Accordingly, oil is drawn from reservoir 15 through booster pump 27 and check valve 21 into the pump inlet port 19 and is forced out of pump 10 through port 16 and check valve 17 into the inlet port 33 of fluid motor 14. Thus, despite the reversal of direction of rotation of wheel 11 and pump 10, fluid motor 14 continues to be driven in the same direction as before. Consequently, generator 32 is always driven in the same direction and thus functions properly. Check valve 18 prevents the oil under pressure from returning to reservoir 15 and check valve 20 prevents short-circuiting of the pumping system, since the oil under pressure cannot pass through this valve into suction port 19. Filter 25, of course, performs the usual function of cleaning the oil which flows through it and, as described above, relief valve 22 prevents the buildup of excess pressure at the inlet port 23 of the fluid motor.

Fig. 2 illustrates a typical electrical distribution system which may be employed in conjunction with the invention; the electrical generator 32 is completely conventional in design and may comprise any one of a number of alternating or direct-current generators available as stock items from various manufacturers. In the illustrated apparatus, generator 32 is a low voltage D.C. generator and may for example comprise the DC. generator manufactured by Delco Remy Division of General Motors Corporation under model designation X-2390. A suitable alternator is that manufactured by the Leece-Neville Company under type designation 5060-6A6. Generator 32 is electrically connected to a conventional voltage regulator 40 in the usual manner; for example, regulator 40 may comprise the standard commercial regulator manufactured by the Delco Remy Company under model designation 118544 or, if a small alternator is used, may constitute the Leece-Neville regulator type 32-68R6 used in conferred mounting arrangement for pump 10 of hydraulic system of Fig. 1; this mounting arrangement constitutes an important feature of the invention in that it permits mounting of the pump directly on a railway car or other vehicle journal without exceeding the clearance requirements for the car. In these figures, the journal 50 for railway car wheel 11 is shown extending into the usual journal box '51; this portion of the apparatus is of standard More the usual axial spline socket 52 into which a spline bushing 53 is fitted. Bushing 53 may be press-fittedinto the socket or may be otherwise mounted therein in such a manner that the bushing is constrained to rotate with the journal.

A drive shaft assembly 54 comprising two drive shaft sections 55 and 56 is included in the apparatus of Figs. 3 and 4; as indicated in Fig. 3, sections 55 and 56 of the shaft are mechanically coupled to each other by a flexible coupling 57 and the end of shaft section 55 opposite the flexible coupling is provided with spline grooves to fit into the splined portion of bushing 53 so that the drive shaft assembly may be rotated in response to rotation of journal -50. A suitable seal, not shown, may be emshaft section 56 opposite flexible coupling 57 and to permit rotational movement of the drive shaft assembly. A second bearing 63 may also be included in gear box 12 to provide additional support for the drive shaft assembly and to maintain it in alignment. A beveled drive gear 64 is mounted on drive shaft assembly 54, being positioned on shaft section 56 intermediate bearings 62 and 63. Drive gear 64 is mounted in meshing engagement with a pinion gear 65 which is mounted upon the operating shaft 66 of fluid pump 15. Pump 16 is supported upon gear box 12; the pump may be mounted upon the gear box by any suitable fastening means such as the bolts 67 illustrated in Fig. 4.

The apparatus illustrated in Figs. 3 and 4 is highly advantageous in conjunction with the invention in that it permits mounting of the pump and gear box directly upon the railway journal box without requiring more than relatively minor modification of the box structure; as indicated in the preceding description, the principal modifications to the journal box 51 are the provision of a slightly modified cover 58 and a mounting flange to support gear box 12. The illustrated structure aflords a minimum extension of the box and pump from the end of the journal, thereby avoiding serious difliculties which might otherwise be encountered in meeting the clearance requirements for railway cars. The gear box is extremely compact and, by providing a right angle drive, permits the realization of an arrangement in which the diameter of the pump represents the maximum extension from the railway journal box. Thus, the primary unit of the hydraulic system can be mounted directly on the end of the car axle, takes up no space within the car, and does not interfere with operation of the car in normal service. The two inlet-outlet ports 16 and 19 of pump are located facing upwardly from the pump to permit convenient connection of flexible hoses or other hydraulic connections from the pump to the remainder of the system without entailing any further extension beyond the end of the journal box.

Figs. 5, 6 and 7 show a preferred arrangement for the remainder of the hydraulic and electrical components of the system and provides a clear indication of the compactness and relatively small size which may be achieved. In this apparatus, the manifold 13, motor 14, reservoir 15, and filter 25 are all mounted in a single assembly along with generator 32 and voltage regulator 40. Thus, reservoir is supported upon a bracket 70 and the manifold 13 is supported upon the underside of the reservoir. As indicated in the elevation view of Fig. 6, reservoir 15 and generator 32 are mounted in side-by-side relationship, the generator being supported upon a bracket 71. Fluid motor 14 is supported upon an additional bracket 72 and the motor shaft 73 is connected to the shaft 74 of the generator through a flexible coupling 75 which may be of standard construction. In accordance with standard practice, the generator may be provided with a fan 76 and may be enclosed Within a mesh housing 77.

In this particular arrangement of the apparatus, booster pumps are simultaneously driven from a single car axle pump 27 is located within reservoir 15, being mounted on the base thereof. The filter 25 is supported by the conduits or pipes 80 and 81 which also serve to connect the filter to motor outlet port 24 and to reservoir 15. For convenience in interpreting the drawings, the arrows '82, 83, 84, '85, '86, 37, and 88 have been included in the several views of the apparatus to afford a ready indication of the direction of fluid flow in the various pipes and-conduits. The corresponding arrows indicating direction of fluid flow are similarly numbered in Fig. 1 to provide complete correlation between the schematic and apparatus drawings.

Fig. 8 is a detailed sectional View of the booster pump 27 showing the actual physical location of inlet ports 26 and 30 and outlet port 29. As indicated in the drawing, oil exhausted from motor 14, which is still under pressure, after passing through filter 25, enters booster pump port 26 and passes through a nozzle section into a Venturi tube section 101. Space is provided around the outlet end of nozzle 100 to permit oil to enter tube 101 from the reservoir inlet port 30. Port 29 of the jet booster is,

of course, connected to the suction port on pump 10. Conse- 15 to make up for any loss in operation of the system and assists the suction action ofpump 10 in pulling oil through tube 1111, therebymaterially improving the oil supply to the pump.

Figs. 9 and 10 illustrate another embodiment of a pump mounting arrangement for use in a hydraulic driving system for an electrical generator to be mounted upon a railway car. In this embodiment, the pump drive is coupled to a railway car journal the illustrated railway journal is of the type usually used with anti-friction bearings on passenger cars and other railway cars intended for high speed operation. A conventional splined bushing 152 is suitably mounted within journal .150 and is utilized to couple the railway journal in driving .relationship to a drive shaft 154. Drive shaft 154 extends through the journal box adapter 158 and into a gear box 112. Gear-box 112 includes a housing 160 which is suitably affixed to journal box adapter 158 by a series of bolts 159 or the like,'the end of the gear box housing being covered by a cap section 161. A pair of bearings 162 and 163 are mounted within the gear box housing and are utilized to support the end of shaft 154 opposite journal 150. Preferably, anti-friction bearings are employed for this purpose.

A beveled drive gear 164 is mounted on drive shaft 154 intermediate, bearings 162 and 163 for rotation therewith; drive gear 164 is essentially similar to the corresponding drive gear 64 of the previously described embodiment. The drive gear 164 is supported in meshing engagement with apair of pinion gears 165A and 165B, the two pinion gears being mounted upon the drive shafts 166A and 166B respectively of a pair of reversible pumps 101m and 10GB. As indicated in Fig. l0, pumps 100 A and 100B are each essentially similar to the pump 10 described above in connection with the embodiment of Figs. 3 and 4. Pump 100A includes a pair of-inlet-outlet ports 116A and 119A and is mounted upon gear box 12 by suitable means such as a'series of bolts 167A; similarly, pump 100B includes two inlet-outlet ports 116B and 119B and is bolted to the gear box as indicated at 16713.

In operation, the apparatus of Figs. 9 and 10 is essentially similar to that of Figs 3 and 4 except that two 150. This arrangement is particularly advantageous where it is desired to provide a driving system for an electrical generator of relatively large capacity, since the two pumps may be connected in parallel to a single fluid motor and afford a substantially increased driving capacity as compared with the single pump arrangement.

'Thus, for example, in a given installation in which the electrical load is relatively large, it may be desirable to utilize a generator of substantially greater capacity than the 1 /2 kilowatt 15 volt D.C. generator identified hereinabove. The two-pump varrangement of Figs. 9 and 10 affords a convenient and economical means for driving a much larger generator, such, for example, as a 4 kilowatt 40 volt machine. In all other essential respects, the embodiment of Figs. 9 and 10 may be essentially similar to that described hereinabove.

The electrical generating system of the invention is extremely compact yet highly eflicient and permits actuation of an electrical generator in response to either forward or reverse movement of the railway car or other vehicle in which it is incorporated. In general, the system is capable of operating over a broad speed range without adversely affecting performance of the driving system. For example, assuming a gear ratio of approximately 3:1 in either gear box 12 or gear box 112, the system may be made operable over a speed range of the order of eight to one hundred miles per hour based on the assumption that the wheel diameter is approximately equal to the railway standard of thirty-six inches. In some applications, particularly on passenger or other head-end cars, it may be desirable to utilize a somewhat lower gear ratio or to employ different pump units than those noted above in order to avoid any possibility that the operating speed range of the pump or pumps will be exceeded. The highly eflicient pump drive arrangements illustrated in Figs. 3 and 4 and Figs. 9 and 10 avoid undue extension of the vehicle axleand consequently permit direct connect-ion of the drive pump to the end of the axle or journal without interfering inany way with normal operation of the car. In this respect, it is important to note that the illustrated arrangements may easily be constructed to fall within the standard railroad clearance lines, so that cars equipped with hydraulic drives constructed in accordance with the invention are acceptable for interchange service. Moreover, as indicated in Figs. -7, the system is welladapted to arrangement in a compact assembly and permits the best possible utilization of space with respect to both the hydraulic and electrical components of the system. In this connection, it should be noted that the motor, generator, and reservoir comprising the assembly illustrated in Figs 5-7 may be mounted either within the railway caror underneath the car. Mounting of the generator and motor under the car is advantageous in that it affords better cooling of these devices and saves valuable space within the car which would otherwise have to be devoted to an electrical equipment locker. Servicing of the equipment, on the other hand, is somewhat simplified if it is mounted within the car. If mounting underneath the car is desired, it may be desirable to employ a somewhat shorter filter than that illustrated in these figures in order to cut down the overall height of the assembly and permit fastening of the reservoir to the car. .In adidtion, it may be desirable to change the position of the filler cap 90 for the oil reservoir to permit filling of the reservoir from the side.

I Hence, while I have illustrated and described the preferred embodiment of my invention, it is to be understood that thisis capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.- V I claim:

1. In a railway car having at least one axle and including an electrical distribution system, an electrical generating system comprising: a generator electrically coupled to i said distribution system; a fluid motor coupled in mechanical driving relationship to said generator and having an inletport; a drive shaft mechanically coupled to one end of said axle of said railway car for rotation therewith; a

drive gear mounted on said drive shaft; a reversible fluid pump, operable by rotation of a pump shaft and having a pair of ports'which serve alternately as inlet and outlet ports, depending upon the direction of rotation of sa d pump; a pinion gear mounted on said pump shaft in meshing engagement with said drive gear for rotation therewith; and fluid coupling means interconnecting said pump and said motor, said coupling means comprising conduits individually connecting each of said pump ports to a source of fluid and to said inlet port of said motor, and fluid pressure actuated valve means in said conduits, responsive to the pressure therein, for delivering fluid under pressure from said pump to said inlet port of said motor to actuate said motor for rotation in a givendirection independent of the direction of rotation of said drive and pump shafts.

2. In a railway car having at least one axle, one end of said axle having an internally splined axial socket therein, said railway car further including an electrical distribution system, an electrical generating system comprising: a generator adapted to be electrically coupled to said distribution system; a fluid motor coupled in mechanical driving relationship to said generator and having an inlet port; a drive shaft mechanically engaged within the splined end socket of said axle of said railway car for rotation therewith; a reversible fluid pump, mounted on said railway car adjacent said splined end of said axle and operable by rotation of a pump shaft and having a pair of ports which serve alternately as inlet and outlet ports, depending upon the direction of rotation of said pump; a set of right-angle driving gears mechanically coupling said drive shaft to said pump shaft for rotating said pump shaft in response to rotation of said railway car axle; and fluid coupling means interconnecting said pump and said motor, said coupling means comprising conduits individually connecting each of said pump ports to a source of fluid and to said inlet port of said motor, and fluid pressure actuated valve means in said conduits, responsive to the pressure therein, for delivering fluid under pressure from said pump to said inlet portion of said motor to actuate said motor for rotation in a given direction independent of the direction of rotation of said drive and pump shafts.

3. In a railway car having at least one axle and an axle box enclosing one end of said axle, said one end ,of said axle having an internally splined socket therein,

said railway car further including an electrical distribu tion system, an electrical generating system comprising: a generator adapted to be electrically coupled to said distribution system to energize said system; a fluid motor coupled in mechanical driving relationship to said generator and having an inlet port; a drive shaft mechanically engaged in the splined end socket of said axle on said railway car for rotation therewith; a beveled drive gear mounted on said drive shaft; a gear box, mounted on said axle box of said railway car, substantially encompassing said drive gear; a reversible fluid pump, mounted upon said gear box, operable by rotation of a pump shaft which extends into said gear box in a direction approximately normal to said drive shaft; a beveled pinion gear mounted on said pump shaft in meshmg engagement with said drive gear for rotation therewith; and fluid coupling means interconnecting said' pump and said motor for delivering fluid under pressure from electrically coupled to said distribution system; a fluid motor coupled in mechanical driving relationship to said generator and having an inlet port; a reversible fluid pump, mounted on said axle box of said railway car and having a pair of ports which serve alternately as inlet and outlet ports, depending upon the direction of rotationtof said pump; means for coupling said pump to said end of said axle of said car in mechanical driving relationship; and fluid coupling means interconnecting said pump and said motor, said coupling means comprising conduits individually connecting each of said pump ports to a source of fluid and to said inlet port of said motor, and fluid pressure actuated valve meansin said conduits, responsive to the pressure therein, for delivering fluid under pressure from said pump to said inlet port of said motor for rotation in a given direction independent of the direction of rotation of said pump.

5. In a railway car having at least one, axle and an axle box enclosing one end of said axle, said railway car further including an electrical distribution system, an electrical generating system comprising: a generator electrically coupled to said distribution system; a fluid motor coupled in mechanical driving relationship to said generator; a reversible fluid pump, mounted on said axle box of said railway car; means for coupling said pump to said end of said axle of said car in mechanical driving relationship; a first pair of fluid conduits, individually connecting different respective ports of said pump to the inlet port of said motor; a first pair of check valves, interposed respectively in said conduits, for restricting fluid flow in said conduits to a direction from said pump toward said motor; a second pair of fluid conduits individuall-y connecting the discharge port of said motor to the respective ports of said pump; and a second pair of check valves, interposed respectively in said second conduits, for restricting fluid flow in said second pairs of conduits to a direction from said motor toward said pump, thereby assuring rotation of said motor in a given direction independent of the direction of rotation of said pump.

6. In a railway car having at least one axle and an axle box enclosing one end of said axle, said railway car further including an electrical distribution system, an electrical generating system comprising: a generator electrically coupled to said distribution system; a fluid motor coupled in mechanical driving relationship to said generator and having an inlet port; a pair of reversible fluid pumps, mounted on said axle box of said railway car and each having a pair of ports which serve alternately as inlet and outlet ports, depending upon the direction of rotation of said pump; means for coupling both of said pumps to said end of said axle of said'car in mechanical driving relationship; and fluid coupling means interconnecting both of said pumps, in parallel, to said motor, said coupling means comprising conduits individually connecting each of said pump ports: to a source of fluid and to said inlet port of said motor, and fluid pressure actuated valve means in said conduits, responsive to the pressure therein, for delivering fluid under pressure from said pumps to said motor to actuate said motor for rotation in a given direction independent of the direction of rotation of said pumps.

7. In a railway car having at least one axle and an axle box enclosing one end of said axle, said railway car further including an electrical distribution system, an electrical generating system comprising: a generator electrically coupled to said distribution system; a fluid motor coupled in mechanical driving relationship to said generator; a reversible fluid pump, mounted on said axle box of said railway car and having a pair of inlet-outlet ports; means for coupling said pump to said end of said axle of said car in mechanical driving relationship; a first pair of fluid conduits, individually connecting different respective ports to said pump to the inlet port of said motor; first check valve means, effectively interposed in said first pair of conduits, (for restricting fluid flow in said conduits to a direction from said pump toward said motor, a second pair of fluid conduits individually connecting the discharge port of said motor to the respective ports of said pump; and second check valve means, effectively interposed in said second pair of conduits, for restricting fluid flow in said second pair of conduits to a direction from said motor toward said pump, thereby assuring rotation of said motor in a given direction independent of the direction of rotation of said pump.

References Cited in the file of this patent UNITED STATES PATENTS 910,211 Mann Jan. 19, 1909 2,077,974 Wishart Apr. 20, 1937 2,104,696 Hanson Jan. 4, 1938 2,271,027 Oelkers Jan. 27, 1942 

